Because if they didn't pretend that it was the same to fly a 737 and a 737 max, then they would be required to have pilots get a separate type certification for

Because if they didn't pretend that it was the same to fly a 737 and a 737 max, then they would be required to have pilots get a separate type certification for the max, which is costly for airlines and makes the airlines very reluctant to order the max.